How do I answer my phone?

I know this sounds pathetically basic. I set a phone lock password and encrypted my phone. So any time I want to use it, I need to enter the PIN. When my phone rings, there's a picture of a phone and circles of dots around it, but touching the screen does nothing. On older Tracfones, even when the phone was locked I could answer calls without entering the PIN. So how do I answer an incoming call?

I once swiped that screen the wrong way and cut off the call. It was from a phone store telling me that my new phone had arrived. I had to go to the store to collect it and apologise for not knowing how to do the most basic thing on a smartphone....answer a phone call.